+ mm-damon-core-introduce-damon_call_control-dealloc_on_cancel.patch added to mm-hotfixes-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/damon/core: introduce damon_call_control->dealloc_on_cancel
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-damon-core-introduce-damon_call_control-dealloc_on_cancel.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-core-introduce-damon_call_control-dealloc_on_cancel.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: SeongJae Park <sj@kernel.org>
Subject: mm/damon/core: introduce damon_call_control->dealloc_on_cancel
Date: Mon, 8 Sep 2025 13:15:12 -0700

When damon_call_control->repeat is set, damon_call() is executed
asynchronously, and eventually be canceled when kdamond finishes.  If the
damon_call_control object is dynamically allocated, hence, finding the
place to deallocate the object is difficult.  Introduce a new
damon_call_control field, namely dealloc_on_cancel, to ask the kdamond
deallocates those dynamically allocated objects when those are canceled.

Link: https://lkml.kernel.org/r/20250908201513.60802-2-sj@kernel.org
Fixes: d809a7c64ba8 ("mm/damon/sysfs: implement refresh_ms file internal work")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Yunjeong Mun <yunjeong.mun@sk.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/damon.h |    2 ++
 mm/damon/core.c       |    8 ++++++--
 2 files changed, 8 insertions(+), 2 deletions(-)

--- a/include/linux/damon.h~mm-damon-core-introduce-damon_call_control-dealloc_on_cancel
+++ a/include/linux/damon.h
@@ -636,6 +636,7 @@ struct damon_operations {
  * @data:		Data that will be passed to @fn.
  * @repeat:		Repeat invocations.
  * @return_code:	Return code from @fn invocation.
+ * @dealloc_on_cancel:	De-allocate when canceled.
  *
  * Control damon_call(), which requests specific kdamond to invoke a given
  * function.  Refer to damon_call() for more details.
@@ -645,6 +646,7 @@ struct damon_call_control {
 	void *data;
 	bool repeat;
 	int return_code;
+	bool dealloc_on_cancel;
 /* private: internal use only */
 	/* informs if the kdamond finished handling of the request */
 	struct completion completion;
--- a/mm/damon/core.c~mm-damon-core-introduce-damon_call_control-dealloc_on_cancel
+++ a/mm/damon/core.c
@@ -2479,10 +2479,14 @@ static void kdamond_call(struct damon_ct
 		mutex_lock(&ctx->call_controls_lock);
 		list_del(&control->list);
 		mutex_unlock(&ctx->call_controls_lock);
-		if (!control->repeat)
+		if (!control->repeat) {
 			complete(&control->completion);
-		else
+		} else if (control->canceled && control->dealloc_on_cancel) {
+			kfree(control);
+			continue;
+		} else {
 			list_add(&control->list, &repeat_controls);
+		}
 	}
 	control = list_first_entry_or_null(&repeat_controls,
 			struct damon_call_control, list);
_

Patches currently in -mm which might be from sj@kernel.org are

mm-damon-core-introduce-damon_call_control-dealloc_on_cancel.patch
mm-damon-sysfs-use-dynamically-allocated-repeat-mode-damon_call_control.patch
mm-zswap-store-page_size-compression-failed-page-as-is.patch
mm-zswap-store-page_size-compression-failed-page-as-is-fix.patch
mm-zswap-store-page_size-compression-failed-page-as-is-v5.patch
mm-zswap-store-page_size-compression-failed-page-as-is-fix-2.patch
mm-damon-core-add-damon_ctx-addr_unit.patch
mm-damon-paddr-support-addr_unit-for-access-monitoring.patch
mm-damon-paddr-support-addr_unit-for-damos_pageout.patch
mm-damon-paddr-support-addr_unit-for-damos_lru_prio.patch
mm-damon-paddr-support-addr_unit-for-migrate_hotcold.patch
mm-damon-paddr-support-addr_unit-for-damos_stat.patch
mm-damon-sysfs-implement-addr_unit-file-under-context-dir.patch
docs-mm-damon-design-document-address-unit-parameter.patch
docs-admin-guide-mm-damon-usage-document-addr_unit-file.patch
docs-abi-damon-document-addr_unit-file.patch